Its just a guide, if you were to write a Western novel or screenplay set at a certain date you have a guide for the various archetypes what you can and cannot use.
1880 The practice of illustrating news stories with photographs was made possible by printing and photography innovations that occurred between 1880 and 1897. While newsworthy events were photographed as early as the 1850s, printing presses could only publish from engravings until the 1880s. Early news photographs required that photos be re-interpreted by an engraver before they could be published.